1. Field of the Invention
The present invention pertains to flotation rafts and means for assembly of thereof. The present invention deals with inflatable rafts having flotation chambers defined by flexible rubberized material which is easily heat sealed with respect to similar material at various locations to aid in raft assembly and assembly of individual parts thereof.
Many different parts of inflatable rafts are often assembled using adhesives which have been found to be time consuming during assembly and thus are deemed to be labor intensive. The present invention provides a means for automating many of these sealing operations by allowing heat sealing rather than adhesive sealing, being particularly useful for heat sealing of closed panels with respect to one another. Heat sealing is a significantly advantageous procedure, not only in regard to the minimizing of labor costs but also with regard to the maximizing of the efficiency of the actual seal. Adhesive seals are long known to be subject to possible leakage due to basic human error during the application and curing of these adhesives. The assembly of a flotation raft assembly using primarily heat sealing operations is a distinct advantage. The present invention provides a procedure for allow increased usage of heat sealing in the making of inflatable raft structures.
2. Description of the Prior Art
Many prior art devices have been utilized to provide an inflatable flotation raft apparatus and to cover methods of assembly thereof such as U.S. Pat. No. 2,764,766 patented Oct. 2, 1956 to J. Boyle et al and assigned to The Garrett Corporation on an "Inflatable Life Raft"; and U.S. Pat. No. 2,987,735 patented Jun. 13, 1961 to W. Nail on "Control Of Inflatable Articles"; and U.S. Pat. No. 3,054,124 patented Sep. 18, 1962 to J. Silverstone on "Inflatable Structures"; and U.S. Pat. No. 3,078,201 patented Feb. 19, 1963 to H. Christie and assigned to Midwest Research Institute on a "Seam Structure For A Flexible Bag"; and U.S. Pat. No. 3,664,401 patented May 23, 1972 to L. Trovati and assigned to Dodelino S. A. on a "Method For The Manufacture Of Inflated Articles"; and U.S. Pat. No. 3,729,357 patented Apr. 24, 1973 to H. Swartz and assigned to General Heat Sealing Corporation on a "Thermoplastic Heat Sealing Apparatus"; and U.S. Pat. No. 3,919,027 patented Nov. 11, 1975 to W. Jones and assigned to Rubber Dynamics Corporation on a "Method Of Making Inflatable Life Raft"; and U.S. Pat. No. 3,960,636 patented Jun. 1, 1976 to M. Moffitt and assigned to Mobil Oil Corporation on a "Method And Apparatus For The Production Of Shear Seals In Thermoplastic Materials"; and U.S. Pat. No. 3,995,339 patented Dec. 7, 1976 to M. Kaufman on a "Transition Piece For Use In Inflatable Life Rafts"; and U.S. Pat. No. 4,001,905 patented Jan. 11, 1977 to J. Givens on an "Improved Stabilized Survival Raft"; and U.S. Pat. No. 4,790,784 patented Dec. 13, 1988 to J. Givens and assigned to Givens Buoy Liferaft Co., Inc. on a "Life Raft"; and U.S. Pat. No. 4,828,520 patented May 9, 1989 to J. Baughman et al and assigned to The B. F. Goodrich Company on a "Modular Liferaft"; and U.S. Pat. No. 4,890,569 patented Jan. 2, 1990 to J. Givens and assigned to Givens Buoy Liferaft Co., Inc. on a "Life Raft"; and U.S. Pat. No. 4,934,301 patented Jun. 19, 1990 to R. Harding and assigned to Avon Inflatables Limited on an "Attachment Of Tubes In Inflatable Boats".